John Calvin Commentary Genesis 11:6

"And Jehovah said, Behold, they are one people, and they have all one language; and this is what they begin to do: and now nothing will be withholden from them, which they purpose to do." — Genesis 11:6 (ASV)

Behold, the people is one. Some explain the words in this way: that God complains of a wickedness in men so stubborn that He stirs Himself by righteous grief to execute vengeance. This is not because He is swayed by any emotions, but to teach us that He is not neglectful of human affairs. Just as He watches over the salvation of the faithful, so He is intent on observing the wickedness of the ungodly, as it is said in Psalm 34:16:

The face of the Lord is against them that do evil, to cut off the remembrance of them from the earth.

Others think there is a comparison between the lesser and the greater, as if it had been said, ‘They are until now few and only use one language; what will they not dare, if, because of their multitude, they should become separated into various nations?’

But it rather seems to me that there is a suppressed irony, as if God were proposing to Himself a difficult task in overcoming their audacity. The sense might be, ‘This people is firmly united in a conspiracy, they communicate with each other in the same language; therefore, by what method can they be broken?’

Nevertheless, He ironically smiles at their foolish and hasty confidence, because while men are relying on their own strength, there is nothing which they do not arrogate to themselves.

This they begin to do. In saying that they begin, He intimates that they are making diligent attempts, accompanied by intense fervor, in carrying out the work. Thus, by way of concession, God declares that, assuming matters are so arranged, there would be no interruption to the building.